The present invention relates to a cover for a sump pump opening. More particularly, the present invention relates to a sump cover which can be bolted to the floor directly above the sump crock opening for the purpose of reducing indoor radon levels in residential and commercial buildings.
Previous covers having various types of sealing arrangements are described, for example, in the following U.S. Pats. Nos.: 2,003,770 to Goodhart; 2,358,750 to Walker et al.; 3,248,119 to Smith et al.; 4,101,236 to Meyer; 4,523,407 to Miller; and also in Canadian Patent No. 725,408 issued Jan. 11, 1966.
By the present invention, there is provided a sump crock cover for reducing radon levels in residential and commercial buildings, being well suited for installation on a basement floor directly over the sump pump opening, with the cover being of a generally circular configuration and including near its peripheral edge two spaced apart annular sealing rings which assist in preventing the escape of hazardous gases such as radon enriched soil gas. The cover includes an integral radially extending ribbed section with a central aperture therethrough for the purpose of receiving a flexible grommet which provides a seal around sump discharge piping and electrical wiring.
In one embodiment, the cover is in the form of a 22 inch diameter reinforced polyvinyl chloride (PVC) disk which is installed directly over a standard 18 inch diameter residential sump pump opening. The sump cover is constructed so that it may be bolted to the concrete slab directly above the sump crock opening. The cover does not in any way hinder normal operation of the sump pump.
The primary function of the sump crock cover of the present invention is to reduce indoor radon levels in residential and commercial buildings. This is accomplished by physically decoupling the barometric pressure gradient which exists above and below a concrete foundation slab. A pair of rubber O-rings provide an airtight seal between the sump lid and the concrete floor, while a flexible grommet provides the seal around the sump discharge piping and the electrical wiring. The cover prevents radon-enriched soil gas from being drawn from the soil beneath the slab, passing unimpeded through the sump opening, concentrating in the basement area and ultimately distributing radon throughout the entire indoor environment.
In addition to reducing the influx of soil gas radon, the sump lid has other potential benefits in residential basements or subgrade environments. These benefits include: (1) reduction of injuries and/or chance of electrical shock caused by open (uncovered) sump crocks and sump motors; (2) increase in usable floor space in the vicinity of the sump; (3) reduction of indoor odors caused by standing water or storm water discharge into the sump pit; and (4) reduction of other noxious or toxic indoor pollutants such as methane or hydrogen sulfide via soil gas influx through open sump pits.